High-pressure mixed streams that include both hydrogen sulfide and carbon dioxide may be generated as a result of a variety of different industrial processes. As an example, certain hydrocarbon wells may produce a product hydrocarbon stream that includes hydrocarbons, hydrogen sulfide, and carbon dioxide. Such a product hydrocarbon stream also may be referred to herein as a sour gas stream. It may be desirable, or even necessary, to separate the hydrocarbons from the hydrogen sulfide and the carbon dioxide before economic or efficient use of the product hydrocarbon stream may occur. Such a separation process may generate a purified hydrocarbon stream, which includes a lower concentration of hydrogen sulfide and/or a lower concentration of carbon dioxide when compared to the raw hydrocarbon stream, and a byproduct stream, which includes a higher concentration of hydrogen sulfide and/or a high concentration of carbon dioxide when compared to the product hydrocarbon stream.
The byproduct stream may be generated at an elevated pressure and may be referred to herein as a high-pressure mixed stream. Under certain circumstances, it may be desirable to separate the hydrogen sulfide in the high-pressure mixed stream from the carbon dioxide in the high-pressure mixed stream. As an example, the carbon dioxide may be injected into a subterranean formation; however, it may be undesirable to inject the hydrogen sulfide into the subterranean formation.
Traditionally, such separation of hydrogen sulfide from carbon dioxide has been performed at relatively lower pressures, which generally requires that the carbon dioxide be pressurized, such as via a compressor, prior to being injected into the subterranean formation. Such pressurization of the carbon dioxide may be expensive and/or energy-intensive. Thus, there exists a need for improved systems and methods for separating hydrogen sulfide from carbon dioxide in a high-pressure mixed stream.